Enhanced energy storage of polyvinylidene fluoride‐based nanocomposites induced by high aspect ratio titania nanosheets

To enhance the discharge energy density (Ue) of polyvinylidene fluoride (PVDF), two‐dimensional (2D) titania nanosheets (TNSs) with high aspect ratio were introduced into PVDF. The results show that the TNSs are uniformly dispersed in matrix and the existence of matrix‐filler interface is confirmed by small angle X‐ray scattering. Introducing of high aspect ratio TNSs is beneficial to enhance the concentration of polar β‐phase and interfacial polarization, which can improve the permittivity (εr) of nanocomposites. Meanwhile, the shape of 2D TNSs plays an important role in enhancement of breakdown strength (Eb). The εr and Eb of the nanocomposites are two significant factors of their high energy storage performance. Therefore, the Ue increases to 0.32 J/cm3, which is 28% higher than that of pure PVDF (~0.25 J/cm3). The energy efficiency of this typical nanocomposite is similar as that of pure PVDF (~90%). This work might provide a method of fabricating promising energy storage dielectric materials. High aspect ratio titania nanosheets (TNSs) were fabricated by the top‐down exfoliation method and were added into polyvinylidene fluoride (PVDF) matrix to enhance the energy storage performance of materials. The energy density and energy storage efficiency are simultaneously improved. This work might provide a method of fabricating promising energy storage dielectric materials.